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Raman spectroscopy was applied on nanostructured ZnFe2O4 system in order to correlate its structural, chemical, and vibrational properties to the functional behaviour, in view of the high sensitivity of the Raman probe to the cationic order in iron oxides. In particular we investigated pure and Ga/Mg doped zinc ferrite nanoparticles synthesised by co-precipitation route by means of Raman spectroscopy with a particular focus on the correlation between their structural and magnetic properties. We firstly studied the homogeneity of the samples at the micrometer scale and their stability under laser irradiation disregarding the presence of spurious iron oxides in favour of a highly defective external shell of the nanoparticles. This hypothesis was corroborated by varying the incident laser wavelength therefore changing the investigated volume. Furthermore, we estimated the inversion degree of the spinel structure finding good agreements with the trend of the magnetic features. All the evidence found through Raman spectroscopy are supported by the results obtained with X-Ray Powder Diffraction, Electron Paramagnetic Resonance and SQUID magnetometry.

Controversial data exist about the long-term results of aortic coarctation (AC) repair. This study explored the prevalence and predictors of left ventricular (LV) hypertrophy, late hypertension, and hypertensive response to exercise in 48 subjects (age, 15.1 ± 9.7 years) currently followed in the authors' tertiary care hospital after successful AC repair. Data on medical history, clinical examination, rest and exercise echocardiography, and ambulatory blood pressure monitoring were collected. The time from AC repair to follow-up evaluation was 12.9 ± 9.2 years. The prevalence of LV hypertrophy ranged from 23 to 38 %, based on the criteria used to identify LV hypertrophy, and that of concentric geometry was 17 %. One sixth of the patients without residual hypertension experienced late-onset hypertension. One fourth of those who remained normotensive without medication showed a hypertensive response to exercise. Age at AC repair was the strongest independent predictor of LV hypertrophy, defined using indexation either for body surface area (odds ratio [OR], 1.03; p = 0.0090) or for height(2.7) (OR 1.02; p = 0.029), and it was the only predictor of late hypertension (OR 1.06; p = 0.0023) and hypertensive response to exercise (OR 1.09; p = 0.029). The risk of LV hypertrophy was 25 % for repair at the age of 3.4 years but rose to 50 and 75 % for repair at the ages of 5.9 and 8.4 years, respectively. Similar increases were found for the risk of late-onset hypertension and hypertensive response to exercise. A considerable risk of LV hypertrophy, late hypertension, and hypertensive response to exercise exists after successful AC repair. Older age at intervention is the most important predictor of these complications.

Chylothorax may be spontaneous or a complication of thoracic surgery. Treatment of this potentially harmful condition is not well established and may comprise dietary interventions and surgery. Somatostatin seems effective in the management of chylothorax, although its mechanism of action is unclear. Conclusion: octreotide, a somatostatin analogue, may be effective in the treatment of post-operative chylothorax.

Hearts with one underdeveloped and one dominant ventricle form a spectrum of anomalies extending from the heart with two clearly adequate chambers to those with a true single ventricle. An angiographic concept of grouping such hearts is presented. 129 patients with unequal ventricles underwent catheterization and cineangiography between 1974 and 1983. The age at first catheterization ranged from one day to 24 years (mean 3.9 years). Male-female ratio was 2:1. Five groups of hearts (with their relative frequencies in the spectrum) were established: (1) dominant left ventricle (53%); (2) dominant right ventricle (20%), each with normally related chambers; (3) dominant left ventricle (20%); (4) dominant right ventricle (3%), each with ventricular inversion; (5) true single ventricle (5%). The incidence of atrial anatomy, venous return, intracardiac connections and associated lesions within each group was assessed. From the standpoint of deranged physiology as well as surgical implications there are more similarities than differences among these hearts. The fact that one ventricle will not generate an adequate stroke volume after repair is overwhelmingly more important than most other considerations. For the diagnostic and surgical approach, we believe that the system offers many advantages.

Dispersion curves of magnetostatic waves in axially magnetized YIG cylinders have been experimentally obtained in the frequency range (2÷11) GHz at room temperature. The experimental results are in very good agreement with the theoretical predictions of Joseph and Schlomann even in the region of long wavelengths. In particular, the surface modes have been experimentally demonstrated. The methods of investigation are described and the results are discussed in comparison with the theory.

An upgraded GARFIELD + Ring Counter (RCo) apparatus is presented with improved performances as far as electronics and detectors are concerned. On one side fast sampling digital read out has been extended to all detectors, allowing for an important simplification of the signal processing chain together with an enriched extracted information. On the other side a relevant improvement has been made in the forward part of the setup (RCo): an increased granularity of the CsI(Tl) crystals and a higher homogeneity in the silicon detector resistivity. The renewed performances of the GARFIELD + RCo array make it suitable for nuclear reaction measurements both with stable and with Radioactive Ion Beams (RIB), like the ones foreseen for the SPES facility, where the Physics of Isospin can be studied., Comment: 13 pages, 19 figures - paper submitted to Eur. Phys. J. A